In many fields of surgery, for example orthopaedics, traumatology, spine surgery and dental surgery different tools, such as screwdriver shafts, drills, awls, probes, chisels, rasps are combined with handles.
In order to reduce costs, weight of instrument sets and number of instruments, tools are often designed as modular systems, featuring a small number of handles in different sizes and types which may be combined with a large number of different tool-inserts. For quick assembly and disassembly of different tool inserts during surgery, state of the art handles feature quick-couplings.
For example, GB 144,607 (Kunz Otto) discloses a tool with interchangeable blades. An offset portion of a blade provided on one side remote from the operative end bears on a handle and forms a pivot about which it is tilted by a movement of a clamping device. The blade is tilted until its back engages a groove provided at one end of the clamping device.
CN 201759601 U (Ningbo Jiandong Quinqzhou Machinery Technology Co.) describes a medical instrument which may be coupled with different tool-inserts. A handle comprises a slot for engaging a tool-insert, said slot comprising a slidable locking plate which locks the tool insert within the slot.
Existing couplings comprise complex and expensive mechanisms which have to fulfil different functional requirements. The coupling between handle and tool-insert must be able to resist high torsional moments, pull-out forces, compressive forces and impacts exerted to the tool by a surgeon. Furthermore, the coupling must be capable of being cleaned and sterilized prior to further surgeries such as to prevent cross-contamination between patients.
State of the art couplings comprise multiple moving parts in an assembly which may not be disassembled. Blood and other tissue may get caught in theses mechanisms and it is impossible to guarantee that all residues are removed before the instrument is used in a next surgery.